2010 international 4300 maxxforce oil pressure at 0.

So here's my problem I have a 2010 International 4300 box truck with a maxxforce 7.6 L engine. My oil pressure gauge is showing 0 in the light is on which is making the check engine light come on. I don't have any oil pressure issues because the truck is still running but the light and the sound can become annoyed. So I went YouTube searching and thought I had located the issue purchased a new sensor offline but the sensor that I took off turned out not to be the right one go figure. Not to mention I broke that one so I had to replace it which was 90 bucks. So as I continue to check all over the engine I thought I had found it unscrewed it noticed it was full of Gunk cleaned it out put the new one on still nothing. Any help???

 

My oil pressure gauge goes up and down every few minutes. When it goes up the checkn engine light goes off but when it goes down it cuts back on. So im guessing thats the issue just was hoping it was just the sensor and not wiring